Narrow-band Imaging, Autofluorescence Imaging and Gastroesophageal Reflux Disease

Diagnostic Value of Narrow-band Imaging, Autofluorescence Imaging & White-light Imaging on Gastroesophageal Reflux Disease

Aim of this study is to compare the efficacy of narrow band imaging (NBI) and autofluorescence imaging (AFI) to distinguish subtle mucosal change related to acid reflux that is not visible in standard white light imaging (WLI) endoscopy, and help indicating the diagnosis of gastroesophageal reflux disease (GERD).

GERD is a common condition that develops when the reflux of gastric and/or duodenal contents causes troublesome symptoms with or without mucosal damage or complications. Despite the high prevalence of GERD in the general population, up to 60% of patients with reflux symptoms is insufficiently characterized as having normal endoscopic finding based on standard WLI endoscopy: non-erosive reflux diseases (NERD).

NBI is an optical-digital imaging technology that uses two specific narrow-banded shot wavelength lights (400-430 nm and 525-555 nm) instead of broad band white light. The NBI contrasts surface structure and vascular architecture of the superficial mucosa and facilitates evaluation of indistinct mucosal morphology. AFI produces real-time computed images of endoscopically detected autofluorescence emitted from endogenous fluorophores in the digestive tract (collagen, nicotinamide, adenine dinucleotide, flavin, and porphyrins) caused by light excitation. The AFI can identify lesions due to differences in tissue fluorescence properties that are not detectable by standard WLI. Hence, our hypothesis is that new endoscopic imaging i.e. NBI and AFI would help to identify subtle mucosal change which indicates the diagnosis of GERD

1. Inclusion criteria

   • GERD symptom: heartburn or regurgitation (either one) at least 2 days a week
   • Presence of symptom for longer than 1 month before screening
   • Provision of written informed consent

2. Exclusion criteria:

   • Any known esophageal disease or disorder, other than reflux esophagitis
   • Active or healing gastroduodenal ulcer (except scars)
   • History of esophageal or gastric surgery.
   • Clinically significant heart, lung, liver or kidney disease
   • Allergy to proton-pump inhibitor
   • Pregnancy